Method of making a hectographic master

ABSTRACT

A master for hectographic printing is made by advancing a paper sheet or tape having an obverse and reverse side in incremental steps past an operating station. At the same time, a carrier web having a thermo-melting color layer is similarly moved past the operating station at which latter is brought into contact with the reverse side of the paper, whose obverse side is sensitized so as to change color when subjected to heat. The obverse side is thereupon contacted at the station with heated instrumentalities which produce local color changes in form of indicia, and the heat passing through the paper causes corresponding local portions of the color layer to melt and adhere to the reverse side of the paper which faces the carrier web, thus producing on this side of the paper mirror-reversed replicas of the indicia, which replicas can subsequently be used for hectographic printing.

United States Patent [1 1 Ritzerfeld Jan. 14, 1975 METHOD OF MAKING AHECTOGRAPHIC MASTER [76] Inventor: Gerhard Ritzerfeld,Schorlemer Allee14, 1000 Berlin 33, Germany [22] Filed: Mar. 30, 1973 [21] .Appl. No.:346,701

[30] Foreign Application Priority Data Apr. 12, 1972 Germany 2218267[52] US. Cl 101/467, 101/469, 346/135 [51] Int. Cl B4lm 5/18 [58] Fieldof Search 101/463, 1, 469, 470, 471, 101/467, 468; 346/76 R, 135;219/216 Primary ExaminerClyde I. Coughenour Attorney, Agent, orFirm-Michael S. Striker [57] ABSTRACT A master for hectographic printingis made by advancing a paper sheet or tape having an obverse and reverseside in incremental steps past an operating station. At the same time, acarrier web having a thermomelting color layer is similarly moved pastthe operating station at which latter is brought into contact with thereverse side of the paper, whose obverse side is sensitized so as tochange color when subjected to heat. The obverse side is thereuponcontacted at the station with heated instrumentalities which producelocal color changes in form of indicia, and the heat passing through thepaper causes corresponding local portions of the color layer to melt andadhere to the reverse side of the paper which faces the carrier web,thus producing on this side of the paper mirrorreversed replicas of theindicia, which replicas can subsequently be used for hectographicprinting.

5 Claims, 2 Drawing Figures WENI JAH 1 4197:;

METHOD OF'MAKING A HECTOGRAPI-IIC MASTER BACKGROUND OF THE INVENTION Thepresent invention relates to masters for hectographic printing, and moreparticularly to an improved master of this type and to a method ofmaking the same.

It is already known to pass a thermally sensitive carrier past anoperating station where it is contacted by heated instrumentalities, forinstance electrically resistance-heated wires or the like, which recordimages on the carrier by causing localized color changes in thesensitized surface of the carrier. Indicia, such as symbols, letters,numerals or the like, can be recorded in this manner. It is customary toutilize a recording head having a number of the heatableinstrumentalities so combined that each of the instrumentalities willform a dot on the sensitized surface of the carrier, with the overallformation of the particular indicia being effected by electricallyheating only those instrumentalities of the head whose dots togetherwill produce the outline or shape of the desired indicium.

The above approach is a well-established part of the art and readilypermits the formation of any desired type and number of indicia. Thesecan, of course, subsequently be read off the carrier.

However, there are many instances where it is desirable to furtherdisseminate the thus-recorded information. Naturally, the carrier withthe indicia thereon SUMMARY OF THE INVENTION It is, accordingly, anobject of the present invention to provide a method of recording indiciain the aforementioned manner on a carrier which at the same timeconstitutes a master that can be used for subsequent hectographicprinting of the thus-recorded indicia.

An additional object of the invention is to provide such a method whicheliminates all intermediate steps required for reproducing the recordedindicia, so that the latter can be produced directly from the carrier onwhich they have been recorded and which also serves as theaforementioned master.

Another object of the invention is to provide an improved master forhectographic printing.

In keeping with the above objects, and with others which will becomeapparent hereafter, one feature of the invention resides in a methodwherein a paper web and a carrier having a thermo-melting color layerthereon are advanced in incremental steps past an operating station. Thecolor layer is contacted with one side of the paper web at thisoperating station, and indicia are thermally produced in the paper webat another side thereof while to the one side there are simultaneouslyadhered portions of the color layer which form on this one sidemirror-reversed replicas of the indicia.

Thus, these mirror-reversed replicas of the indicia can be used at anydesired time either immediately after their formation or afterexpiration of a greater or lesser period of time to hectographicallyprint copies of the information recorded on the carrier/master in formof the aforementioned indicia.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a somewhat diagrammatic sideview of an arrangement for carrying out the novel method; and

FIG. 2 is a fragmentary partly sectioned detail view of FIG. 1, on anenlarged scale.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Before entering into a detaileddiscussion of the drawing it is recalled once more that the principle ofproducing indicia by causing localized portions of a heat-sensitivecarrier to change color through contacting them with a heatedinstrumentality is well established in the art. A recording head usedfor such purposes usually is provided with a plurality of electrodes inform of wires or small rods which are arranged in form of a grid orraster. The free ends of these rods contact the thermally sensitivecarrier and, when a particular rod is electrically energized, its freeend in contact with the carrier will cause the latter to becomediscolored locally, namely forming a dot. The rods are usually arrangedin form of a grid having seven lines of five rods each, so tht such ahead may have 35 rods and can correspondingly produce 35 dots. Ofcourse, the number may be greater or lesser. To produce a particularindicium, such as a letter, numeral or the like, selected ones of therods are heated so as to produce a number of dots which together formthe outline of the indicium in question. The selection of the rods to beheated is carried out bya signal generator which can be controlled froma keyboard or from an automatic programming device. The indicia thusformed are of course legible but cannot be conveniently reproduced, forthe reasons set forth earlier.

With this in mind it will be seen that FIGS. 1 and 2 show an arrangementfor carrying out the novel method, that is for producing a hectographicmaster at.

the same time as indicia are being recorded, with the carrier on whichthey are recorded serving simultaneously as the hectographic master.Reference numeral 1 in the drawing designates the finished master forhectographic printing. Reference numeral 2 designates a thermalactivatorhaving a recording head 2a of the type discussed earlier andwell known to the art. Selection of the particular rods which are to beenergized in the head 2a to produce a given indicium is controlled by anon-illustrated coding matrix in a data processing system, that is via apre-selected program. This is too well known to require detaileddiscussion and does not in itself form a part of the present invention.The head 2a may have the aforementioned raster arrangement of sevenlines of rods, each line having five of the rods so that the head canproduce 35 dots. It is located, or rather the free ends of the rods arelocated, immediately adjacent the heat-sensitive paper web la on whichthose of the rods which are activated produce respective dots thetotality of which forms an indicium 3.

The paper web la is provided with a heat-sensitive layer 112 which willchange color where it is subjected to the heat produced at the free endsof the respective rods, thus forming the dots. Thus far, there isnothing novel involved.

However, in accordance with the present invention, it is desired thatthe paper web not only be provided with a recording of the respectiveindicia but that it at the same time be constituted as a master capableof melting, that is, when subjected to localized heat, local portions ofthe substance melt and are transferred to the web 1a. Such substancesare well known, and'the web 4 may for instance be produced in accordancewith the disclosure in my prior US. Pat. No. 3,096,711.

The web 4 is withdrawn from a supply roll 5 and taken up on a take-uproll 7. Intermediate these rolls is locateda pressure roller 6 whichengages the web directly opposite the recording head 2a. The carrier la,which may for instance be provided with leporellofolds, has theaforementioned heat-sensitive layer lb. It may be stored in a container8 from which it is made to pass between the web 4 (so that the latter islocated between the paper web la and the roller 6) and a pressure roller9 so that its side 1a" comes in contact with the coloring substancelayer 4b of the web 4.

The carrier 1a and the web 4 are moved in incremental steps past thehead 2a. This means, of course, that they must be moved past the head atidentical speeds, for which purpose an electromotor 10 is provided whichis controlled by the same programming system that also controls theactivation of the various rods in the head 24a. The motor 10 drives theroller 6, a transport roller 16 for the carrier la and subsequently themaster 1 which is deposited in a receptacle 17, and the roller 7, forwhich purpose a timing belt 11 and timing gears 12, l3, l4 and 15 areprovided which cooperate with the belt 11. A transport roller 18cooperates with the roller 16, and rollers 19 and 20 are provided whichserve as guide rollers for the carrier 1a and subsequently the master 1.FIG. 2 shows on an enlarged scale how the indicia 3 are formed on theside la of the carrier la by the head 2, and how simultaneously themirror-reversed replicas ofthe indicia 3 are formed at the reverse sidela" of the carrier la. The heat which forms the replicas 3 at the sidela passes through the carrier 1a and locally melts the coloringsubstance of the layer 4b which is in contact with the side la", so thatthe melted portions adhere to the side la" in registry with the indicia3, forming mirror-reversed replicas 4b on the side la". It is thesereplicas which, after the now completed master 1 is separated from theweb 4, permit direct hectographic printing of the recorded information.

The head 2a may be made to advance axially along the roller 6 to produceindividual indicia 3 (the socalled bit-serial operation"), or it maybestationary and extend over the entire axial length of the roller 6 andproduce entire lines of indicia simultaneously (the so-calledbit-parallel operation). Both of these approaches are already known fromthe art.

It goes without saying that the carrier la can be in form of anelongated web, or in form oflindividual sheets, and the same isevidently also true of the web 4. t

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofconstructions differing from the types described above.

While the invention has been illustrated and described as embodied inthe making of a hectographic master, it is not intended to be limited tothe details shown, since various modifications and structural changesmay be made without departing in any way from the spirit of the presentinvention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to beprotected by Letters Patent is:

1. A method of making a master for a hectographic copying process,comprising the steps of simultaneously advancing a non-transparent paperweb having an obverse and a reverse side and provided with a thermallysensitive layer on its obverse side, together with a carrier web havinga thermally transferably color layer, in incremental steps past anoperating station; contacting said color layer with said reverse side ofsaid paper web at said operating station; and applying heat to selectedportions of said obverse side of said paper web at said operatingstationso as to-produce trueimage indicia on said obverse side bylocalized discoloration of said thermally sensitive layer and tosimultaneously transfer to said reverse side portions of said colorlayer corresponding in shape to said indicia, said portions of saidcolor layer adhering to said reverse side and forming thereonmirror-image replicas of said indicia which are subsequentlytransferable to copy sheets in a hectographic copying process as trueimages of said indicia.

2. A method as defined in claim l,'wherein the step of applying heatcomprises contacting said ,paper web at said obverse side with heatedindicia-forming instrumentalities.

3. A method as defined in claim 1; and further comprising the'final stepof separating said paper web with said indicia and replicas formedthereon, from said carrier web and advancing it to a collecting station.

4. A method as defined in claim 1, wherein the step of applying heatcomprises contacting said obverse side of said paper web with heatedindicia-forming instrumentalities, and contacting a side of said carrierweb which faces away from said paper web with a roller located oppositesaid instrumentalities.

5. A method as defined in claim 4, wherein said carrier web is a tape;and wherein the step of advancing said carrier web comprises withdrawingthe same from a supply roll past said roller, and forwarding the carrierto a take-up roll.

1. A method of making a master for a hectographic copying process,comprising the steps of simultaneously advancing a nontransparent paperweb having an obverse and a reverse side and provided with a thermallysensitive layer on its obverse side, together with a carrier web havinga thermally transferably color layer, in incremental steps past anoperating station; contacting said color layer with said reverse side ofsaid paper web at said operating station; and applying heat to selectedportions of said obverse side of said paper web at said operatingstation so as to produce true-image indicia on said obverse side bylocalized discoloration of said thermally sensitive layer and tosimultaneously transfer to said reverse side portions of said colorlayer corresponding in shape to said indicia, said portions of saidcolor layer adhering to said reverse side and forming thereonmirror-image replicas of said indicia which are subsequentlytransferable to copy sheets in a hectographic copying process as trueimages of said indicia.
 2. A method as defined in claim 1, wherein thestep of applying heat comprises contacting said paper web at saidobverse side with heated indicia-forming instrumentalities.
 3. A methodas defined in claim 1; and further comprising the final step ofseparating said paper web with said indicia and replicas formed thereon,from said carrier web and advancing it to a collecting station.
 4. Amethod as defined in claim 1, wherein the step of applying heatcomprises contacting said obverse side of said paper web with heatedindicia-forming instrumentalities, and contacting a side of said carrierweb which faces away from said paper web with a roller located oppositesaid instrumentalities.
 5. A method as defined in claim 4, wherein saidcarrier web is a tape; and wherein the step of advancing said carrierweb comprises withdrawing the same from a supply roll past said roller,and forwarding the carrier to a take-up roll.